8131891853 has 2 divisors, whose sum is σ = 8131891854. Its totient is φ = 8131891852.

The previous prime is 8131891847. The next prime is 8131891897. The reversal of 8131891853 is 3581981318.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7409249929 + 722641924 = 86077^2 + 26882^2 .

It is a cyclic number.

It is not a de Polignac number, because 8131891853 - 2²² = 8127697549 is a prime.

It is a super-2 number, since 2×8131891853² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 8131891798 and 8131891807.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8131891253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4065945926 + 4065945927.

It is an arithmetic number, because the mean of its divisors is an integer number (4065945927).

Almost surely, 2^8131891853 is an apocalyptic number.

It is an amenable number.

8131891853 is a deficient number, since it is larger than the sum of its proper divisors (1).

8131891853 is an equidigital number, since it uses as much as digits as its factorization.

8131891853 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 207360, while the sum is 47.

The square root of 8131891853 is about 90177.0029053971. The cubic root of 8131891853 is about 2010.9311340576.

The spelling of 8131891853 in words is "eight billion, one hundred thirty-one million, eight hundred ninety-one thousand, eight hundred fifty-three".